randomized_benchmarking_seq(nseeds=1, length_vector=None, rb_pattern=None, length_multiplier=1, seed_offset=0, align_cliffs=False, interleaved_gates=None, interleaved_elem=None, is_purity=False, group_gates=None, rand_seed=None)¶
Generate generic randomized benchmarking (RB) sequences.
int) – The number of seeds. For each seed the function generates a separate list of output RB circuits.
Length vector of the RB sequence lengths. Must be in ascending order. RB sequences of increasing length grow on top of the previous sequences.
length_vector = [1, 10, 20, 50, 75, 100, 125, 150, 175]
length_vector = Noneis the same as
length_vector = [1, 10, 20]
A list of the lists of integers representing the qubits indexes. For example,
[[i,j],[k],...]will make simultaneous RB sequences, where there is a 2-qubit RB sequence on qbits Qi and Qj, and a 1-qubit RB sequence on qubit Qk, etc. Each qubit appers at most once. The number of qubits on which RB is done is the sum of the lists sizes.
rb_pattern = []or
rb_pattern = None– create a 1-qubit RB sequence on qubit Q0.
rb_pattern = [[0,1]]– create a 2-qubit RB sequence on qubits Q0 and Q1.
rb_pattern = [,[6,4]]– create RB sequences that are 2-qubit RB for qubits Q6 and Q4, and 1-qubit RB for qubit Q2.
int]]) – An array that scales each RB sequence by the multiplier.
int) – What to start the seeds at, if we want to add more seeds later.
Trueadds a barrier across all qubits in the pattern after each set of group elements (not necessarily Cliffords).
Note: the alignment considers the group multiplier.
str]]]) – Deprecated. Please use the
interleaved_elemkwarg that supersedes it.
None]) – A list of QuantumCircuits or gate objects or group elements that will be interleaved. It is not
Noneonly for interleaved randomized benchmarking. The lengths of the lists should be equal to the length of the lists in
Trueonly for purity randomized benchmarking (default is
is_purity = Truethen all patterns in
rb_patternshould have the same dimension (e.g. only 1-qubit sequences, or only 2-qubit sequences), and
length_multiplier = None.
On which group (or set of gates) we perform RB (the default is the Clifford group).
group_gates='Clifford'– Clifford group.
group_gates='Non-Clifford'– CNOT-Dihedral group.
None]) – Optional. Set a fixed seed or generator for RNG.
- Return type
(typing.List[typing.List[qiskit.circuit.quantumcircuit.QuantumCircuit]], typing.List[typing.List[int]], typing.Union[typing.List[typing.List[qiskit.circuit.quantumcircuit.QuantumCircuit]], NoneType], typing.Union[typing.List[typing.List[typing.List[qiskit.circuit.quantumcircuit.QuantumCircuit]]], NoneType], typing.Union[int, NoneType])
A tuple of different fields depending on the inputs. The different fields are:
circuits: list of lists of circuits for the RB sequences (a separate list for each seed).
xdata: the sequences lengths (with multiplier if applicable).
circuits_interleaved: (only if
None): list of lists of circuits for the interleaved RB sequences (a separate list for each seed).
circuits_purity: (only if
is_purity=True): list of lists of lists of circuits for purity RB (a separate list for each seed and each of the \(3^n\) circuits).
npurity: (only if
is_purity=True): the number of purity RB circuits (per seed) which equals to \(3^n\), where n is the dimension.
ValueError – if
ValueError – if
rb_patternis not valid.
ValueError – if
length_multiplieris not valid.
ValueError – if
interleaved_elemtype is not valid.
Generate simultaneous standard RB sequences.
length_vector = [1,10,20] rb_pattern = [[0,3],,] length_multiplier = [1,3,3] align_cliffs = True
Create RB sequences that are 2-qubit RB for qubits Q0 and Q3, 1-qubit RB for qubit Q1, and 1-qubit RB for qubit Q2. Generate three times as many 1-qubit RB sequence elements, than 2-qubit elements. Place a barrier after 1 group element for the first pattern and after 3 group elements for the second and third patterns. The output
xdatain this case is
Generate simultaneous interleaved RB sequences.
rb_pattern = [[0,3],,] # as a QuantumCircuit: qc_cx = QuantumCircuit(2) qc_cx.cx(0, 1) qc_x = QuantumCircuit(1) qc_x.x(0) qc_h = QuantumCircuit(1) qc_h.h(0) interleaved_elem = [qc_cx, qc_x, qc_h] # or as gate objects: interleaved_elem = [CXGate(), XGate(), HGate()]
Interleave the 2-qubit gate
cxon qubits Q0 and Q3, a 1-qubit gate
xon qubit Q2, and a 1-qubit gate
hon qubit Q1.
Generated purity RB sequences.
rb_pattern = [[0,3],[1,2]] npurity = True
Create purity 2-qubit RB circuits separately on qubits Q0 and Q3 and on qubtis Q1 and Q2. The output is
npurity = 9in this case.